This is the same scene that was shown in the teaser, this time without hiding anything. The Dual Reality essence is here, player can jump from dimension to dimension using the Reality Manipulation Device, and time runs only in the current dimension you are playing. That means anything (physics, NPCs, events, animated textures, particles... all) gets frozen. For this video combine are set to friendly, by the way. You'll see this world in its full splendor in upcoming videos.

Physics and NPCs also can be 'interported' from dimension to dimension in several ways. The sphere is the most basic way. If you want to know details from the other dimension, that's also possible with the interdimensional window, as you may noticed. There's other important tool for navigation and world awareness which will be revealed soon.

As you can see, you'll be controlling Alyx. It's some sort of humble tribute to this character. She had great moments in HL2 and the episodes, yet she never played the leading role. Standard animations are being used, it's not a problem since most of them fit well, however some custom ones are still needed. View can be set to first person with full body awareness or third depending your needs/preferences.

A note about the special fx's. Dual Reality uses some outlining and glow effects, I must thank killermonkey (Golden Eye Source coder) for his outstanding work. He posted a nice article at VDC describing it in detail, later his work inspired me to create the interdimensional window effect (uses stencil buffer too).

Tracking! Although I have no real idea what went on in the video either - watched it muted btw. A couple of us were trying to think of a way of implementing time travel and other awesome alternative stuff into FPS games, but never got any further with our ideas, so this should be interesting :D